ST. PETERSBURG — A 21-year-old St. Petersburg man is in critical condition with life-threatening injuries after his car collided with a school bus Friday morning, police said.

The school bus, on a practice run before school starts Monday, was not carrying any children.

Police say Rashad Haughabook was speeding in a 2006 Chevrolet, traveling west on 18th Avenue S at 44th Street about 10:30 a.m. As the school bus, which was traveling south on 44th Street, entered the intersection, the Chevrolet slid under it from behind, police said. The Chevy then hit the south curb and flipped on its side.

Haughabook was trapped in the car until rescue workers freed him. He was transported to Bayfront Medical Center.